hi, first things first, lose some weight, it'll give you some more confidence. regular exercise or yoga will be helpful. eat and sleep timely and do things you like. when negative thoughts creep in, divert your mind consciously and do something constructive or something that you like rather than sitting and thinking about it. take care

"What you believe you become"  is the what Buddha says. So do learn to practice your thought process in a such you wanted you to become in the future.

Dear friend, Yes. It is true that thought creates reality. Have your thinking positive. Thoughts makes lives. Wishes